According to your site this versin requires no license, but in other places I read that you always need a license to download a binary.
Cloudera used to offer Express edition for Cloudera Data Hub, aka CDH, e.g. CDH 5.x, 6.x
It is part of the platform binaries, so only if you upload a valid license, you will activate the enterprise features, else you can continue using the Express edition free of charge
Since end of Jan 2021, to download all platform binaries, including CDH 5.x, CDH 6.x, HDP and CDP, you need an active Cloudera subscription, details: https://www.cloudera.com/downloads/paywall-expansion.html
So to answer your question
1. you need an active Cloudera subscription to download
2. if you already have the binaries, i.e. CDH 6.3.2, you can continue using the Express edition free of charge